Intergranular cracking in cladding tube of PWR RCCA rodlets

Takanori Matsuoka, Toshio Yonezawa, Minori Tomimatsu, Masahiko Mori, Hisashige Myojin, Yoshiaki Sasaki, Masanori Ootani, Tadahisa Nagata

    Research output: Contribution to journalArticlepeer-review

    8 Citations (Scopus)


    Increase in outer diameter of the rod cluster control assembly (RCCA) rodlets in a PWR plant was observed. Visual inspections of RCCA rodlets with large increases in outer diameter using a fiber scope and hot cell examinations of some RCCA rodlets lead to the following conclusions. 1 The increase in outer diameter was caused by the swelling of the absorber (Ag-In-Cd alloy). 2 At the RCCA rodlet tip, which was exposed to the largest amount of neutron fluence, an axial crack in the cladding tube was observed. 3 From the tensile test of cladding tube material, the uniform tensile strain was reduced to about 1.4% at 320°C due to neutron irradiation. In the slow strain-rate tensile test, intergranular cracking was observed. 4 From the above, it is considered that the axial cracking in the cladding tubes of PWR RCCA rodlets was caused mainly by a decrease in elongation due to neutron irradiation and an increase of hoop strain due to the swelling of the absorber.

    Original languageEnglish
    Pages (from-to)515-523
    Number of pages9
    JournalJSME International Journal, Series A: Mechanics and Material Engineering
    Issue number4
    Publication statusPublished - 1995

    ASJC Scopus subject areas

    • Engineering(all)


    Dive into the research topics of 'Intergranular cracking in cladding tube of PWR RCCA rodlets'. Together they form a unique fingerprint.

    Cite this